1. Technical Field
This invention relates to a film type battery and a layer-built film type battery. The battery of the invention is useful, for example, in an ID card, a portable telephone, a memory card, a pocket bell, or an electric automobile etc.
2. Background Art
A conventional film type battery is shown in FIG. 27. The conventional film type battery included a sealing agent 2 put around a generating element 1 formed by laminating a positive active material, an electrolyte and a negative active material into a layer structure. A positive current collector plate 3 and a negative current collector plate 4 were disposed above and below the generating element 1, and the generating element 1 was then sealed with both current collector plates 3 and 4 bonded by the sealing agent 2. Terminals 5 were formed by leaving the surfaces of selected corners of both current collector plates 3 and 4 as they were and covering the remaining surfaces by synthetic resin or the like.
Such a film type battery was used also as a layer-built film type battery by being laminated in plural layers as shown by FIG. 28.
However, the internal temperature of the film type battery having the foregoing structure sometimes rises resulting in fire or, in the worst case, bursting, when its power consumption becomes large. This defect is also found in the layer-built film type battery having the foregoing structure.